Shock absorber



imi... 2651924;

E. S. AKER SHOCK ABSORBER Filed Nov. 17. 1922 INVENTOR.

Patented stl,-

EVEDER S. KEB, OF GOSHEN, NEW YQRK.

` semen aesoasnr..

Application filed November 17, 1922. Serial No. 601,450.

To all il; hom it may concern Be it known that l; EvnNDEn S. Arian. a citizen of 'the'United States. residino` at Goshen, in the county of @range and vfilate of New York, have invented certainnew and useful Improvements in Shock Absorbers; and l do herebyA declare the following' to be a full. clear, 'andexact description of ther invention, such' will enable others skilled y inder or chamber is compressed so that ad in the art to which it appertains to make and use the same. vreference being had to the accompanying drawings, and to characters of reference marked thereon, which 'form a part of this specification.

This invention. relates. generallyrto iinprovements in shock-absorbers for vehicles, and the .invention has for its principal object to provide an improved shocleabsorlwr comprising a cylinder containing a suitable fluid `and a piston, saidpiston having a normally open by-pass valve, means being provided to actuate the by-pass valve to grad- 'ually close the same as the piston moves downwardly in the cylinder from its normal initial position whereby the flow of fluid from one side of the piston to the other is gradually stopped so that an increasing resistance is opposed to the piston movement .as it approaches the downward limit of its stroke. A further object of the invention is to provide an arra'igement of piston in they cylinder whereby the former is capable of an'upward rebound stroke be.

yond its normal initial position, means also being provided tovactuate the by-pass valve to close the same as the` piston approaches the upward limit ot such rebound stroke. whereby the 'liow of fluid throughthe pist0n ports is checked to oppose an increasingr resistance to such upward rebound stroke. Another object of the invention is to provide in connection with' the upper outer end of the pistonstem an air cylinder or chamber synchronously movable with the fluid piston to cooperate with a fixed piston .attached to the upper end of the fluid cylinder whereby on the downward stroke of said fluid piston the air within said aircylditional resistance is offered to thedownward stroke of said fluid piston while at the same time thevv compression of the air produces a more orv less elastic cushioning e'ect relative to the operation of' the shock ab sorber as a whole.

@ther objects of this invention, not at this time moreparticularly enumerated, will be clearly understood from the following detailed description of the same.

TWith the various objects of this invention in view, the same consists. primarily, in the novel construction and arrangement of shock-absorber for vehicles hereinafter set' forth; and the invention consists, furthermore, in the novel arrangements and combinations of the various devices and parts, as well as in the details of the construction of the same, all of' which will be hereinafter more fully described` and then finally einbodied in the claims appended to this specification.

rlhe invention is clearly illustrated in the' accompanying drawings, in which Y Figure 1 is a longitudinal vertical section illustrating the novel shock-absorber made according to and embodyimcr the principles l of this invention, the operative parts being shown in their normal initial positions; Figure 2 is a horizontal cross section, taken on line 2-2 in Figure lgiFigureB is a longi- .S0v tudinal vertical section illustrating the relation of the operative parts as the fluid piston approaches the limit of its downward, stroke Figure 4 is a horizontal section. taken on linea-4 in said Figure 3: an'd Figure 5 85 is a fragmentary detail longitudinal vertical sectionl taken in a Aplane at right angles ltothe sectional plane of Figure 1.

views, to indicate corresponding parts.

Referring now to said drawings. the ref-4 erence character 6 indicates a Huid containingr cylinder closed at-its bottom end, and having its upper end closed by a detachable cylinder head or cap 7. Said cylinder head or capis provided with a central stuffing-*boxv 8. through which extends the tubular stem 9 of a. piston 1Q movable'in said cylinder 6. A gland 11 lits slidingly into the upper end of 100' the stuffing-box 8 .to engage and hold the packing 12 around the piston stem 9. The upper free end of said` piston stem 9 is rovided with a perforate earv or lug 13. v uitably secured Vin connection with the upper free endA of said piston stem 9 and the ear or. lug 13 is the upper closed end 14 of an air cylinder 15, thelatte'r being of slightly larger internal diameter than the external diameter of the Huid containing cylinder 6, so that the lower openend of the same may pass telescopically over said cylinder 6. The

` reference character 16 indicates a fixed pis:

ton member which is engaged over the stuffing-box 8, and securely clamped or fastened between a shoulder 17 on the upper side of thecylinder head or cap 7 at the base of said stufiing-box and a 'clamp nut 18, the rippen end of said stutling-box 8 being externally threaded to receive said elamp-nut'18. The periphery of said fixed piston member 16 engages the internal walls of said air cylinder as shown in Figures 1 and 8 of the drawn ings. Arranged about the piston stem 9 in termediate the upper end wall 111 ot said air,

. cylinder 15Iand the exteriorend of the gland 11 is a compression spring 19 which holds said gland in operative relation to the packing 12. i

Secured to the bottom end wall of said iiuid containing cylinder 6, in a central longitudinal position so as to extend upvalve ports or openings 21. .i against the bottom of said piston 1() is aA wardly through the interior of said cylinder, with its upper end slidably or telescopically engaged by the lower end ofthe tubular stem 9 "of said piston 10, is a tubular guide-member, 20. Said piston 10 occupies a normal initial position within the cylinderl 6 spacing the same downwardly from the upper end of the said-cylinder for a distance approximating about one-third of the total vlength of said cylinder. Said piston is provided in its body with one or more vertical Registered valve disc 22, also provided with on@l or morevvalv'e ports or openings 23 which aline themselves with the valve ports or openings of said piston 1() when the latter occupies its normal initialposition in the cylinder. Said valve disc 22 is held in operative association with or attachment to the bottom of said piston 10, by means of studs 24 which are fixed to said piston 10 to project downwardly therefrom ythrough concentric or curvillnear slots 25 provided 1n the valve disc 22, the free ends of said studs 24 having enlarged heads 26 for retaining the valve disc in place. As thus mounted and supportedrelative to the bottom o tf'the piston 10, saidvalve disc 22 is free to turn about the axis of the piston and its stem.. The means for producing operative move ment of said valve disc 22 consists of cam grooves 27 provided in the .,walls of said 0uide-member into .which extend lugs 28 tformed to project inwardly Afrom the inner annular periphery of the valve disc 22.

Said camgrooves 27 possess` a downwardly extending lspirally formed portion 27, extending fromthe initial position of the piston downwardly toward the bottom of the cylinder 6, and an upwardly extending spirally formed portion 27 of sharper pitch extendingfrom the initial position o'i the piston upwardly toward the top of the cylinder 6.

i ,ae/ieee "When the piston 10 occupies its normal initial position intermediate the ends of the cylinder G, the lugs 28 of the valve disc 22 engage neutral portions of the cam grooves 27 whereby the valve disc 22l is normally positioned so as to aline its ports 23 with the ports 21 of the 'piston 10. vWhen the pressure or force ot' a shock is transmitted to thepiston stem 9 tending to move the piston 10 downwardly in the cylinder 6, the

fluid beneath the piston will be caused t'o pression of the fluid between'the piston and the bottom of the cylinder as the free flow of such fluid past the lpiston is checked. As a consequence of this yaction shocks are absorbed and gradually reduced in a ver ef-.

icient manner as will be understood. pon

rebound .after the transmission of ashock.

to the absorber, the piston 10 will move upward in the cylinder 6, which movement is accompaniedv by a reverse rotation of the valve disc 22 tending to again open the piston valve ports `21 to the return lowof Huid to the under side of the piston. If, when the piston reaches normal initial position, the rebound` reaction is stron yond its said normalinitial position, then the lugs 28 of the valve disc 22 are carried into operative'en'gagement with the portions 27"- of the cam grooves, whereby the valve disc is turned to close the piston ports 21 as said piston approaches the upper end of the cylinder, and thereby opposes the downward flow of fluidl past the'piston resulting in gradually compressing the fluid .to produce an increasing resistance to such continuous upward` movement of the piston.

y enough yto move 'the piston upwardly in t e cylinder 6 be- This action tends to cushion or reduce the violence of rebound reaction of the parts :served by theshock-absorber and tends to bring said parts easily and quickly back to the normal status quo.

From the above description it will be apparent that my present invention ,provides a very simply constructed shock-absorber which will operate efficiently to absorb both original shocks and violent rebound reac-v tion after absorption of the force of said original shock, the novel piston valvev mechanism being arranged and constructedto operate gradually so as not to produce a too abrupt check of the piston movement or a too sudden compression of the iiuid against which the piston operates. rlhe operation and purpose of the other eatires of my invention, as, e. g., the air cylinder and fixed piston cooperating therewith will be understood without further'reiteration.

I am aware that some changes may be made in thelarrangements and combinations of the various devices andv parts, aswell as in the details of the construction of the same, without departingfrom the scope of my present invention asset forth in the lforegoing specification, and as defined in the appended claims. Hence, l do not limit my invention to the exact arrangements and combinations 'of the several devices and parts as described vin'said foregoing specification, nor do I confine myself tothe exact details of the construction of said parts as illustrated in the accompanying drawings.

l claim l. A shock-absorber comprising a fixed cylinder adapted to contain a fluid, a movable piston therein, a piston stem projecting exteriorly from the upper end of said cylinder, saidv piston having a valve port, a movable valve-disc having a port normally alinedwith said piston valve-port,

m'eans cooperating with said valve-disc for .moving the same to close said` piston valve` port as 'the piston makes its operative descent in said cylinder, aimovable ail cyli` der fixed to the exterior end of said piston stem, the lower open end of which is arranged telescopically over the upper end of said fixed cylinder, and a fixed piston member connected with the u pper end of said fixed cylinder to fit and cooperate with said movable cylinder.

2. A shock-absorbery comprising a fixed cylinder adapted to` contain a fluid, a mov# able piston therein, a' movablefpiston stem .projecting exteriorly from the upper end of said cylinder, said movable piston being normally initially positioned'intermediate the upper and lower ends of said cylinder,

said piston having a valveport, a movable valve-disc having a port normally alined with .said piston valve-port, means coop-y erating with said valve formoving the same to gradually close said piston .valve- :port as the piston descends from normal initial position toward the lower end of said cylinder and also for I'noving the Same to close said piston ,valve-port .asthe `piston ascends from* normal initial position toward the upper end of said cylinder, a movable air cylinder fixed to the exterior end of said piston stem, the lower open end of which is arranged telescopically over the upper end of said fixed. cylinder, and a fixed piston member "connected with the upper end of said fixed cylinder to fit and co1 operate with said movable cylinder.

3. A shock absorber comprising a cylinder, a'piston therein, a tubular piston stem projecting exteriorly from the upper end oi said cylinder, said piston'having a valve-v der,- a piston therein having a valve port,

said piston being normally initially positioned intermediate thel upper and lower ends of said cylinder, va tubular piston stem .projecting exteriorly from the upper end o said cylinder, a movable valve-disc mounted on the under side of said piston to rotate about the vertical axis of said piston and its stem,l said valve-disc having a port normallyy alinedwith said piston valve-port, a guidemember extending upwardly in central longitudinal position from the bottom of said piston, over which said piston and its stem and said valve-disc are slidably engaged, cam-grooves in said uide-member, said cam-grooves. having spirally curved portions extending downwardly from the normal initial positionof said piston toward the lower end of Sa'id cylinder` said `cam grooves having additional spirally curved portions extending vfrom the normal initial posit-ion of said piston upwardly from the normal initial position of. said piston toward the upper end of said cylinder, and 

